1. Field of the Invention
The present invention relates to a printing apparatus and a method for controlling the printing apparatus.
2. Description of the Related Art
Printing apparatuses that perform a process of printing on sheets (paper sheets) are known. Various kinds of sheets are used in the printing process, and are classified by, for example, size, thickness, weight per unit area (hereinafter called grammage), quality (surface smoothness), etc., thereof. The printing apparatuses are demanded to print images with a uniform appearance irrespective of the kind of sheets on which the images are printed in the printing process. To satisfy this demand, a printing apparatus has been proposed which changes an operating state in the printing process in accordance with the kind of the sheet so as to make the appearance of the printed images uniform irrespective of the kind of sheets used in the printing process. When, for example, the printing apparatus is an electrophotographic printer, the operating state of the printing apparatus includes the settings of a pressing force and a fixing temperature applied to fix a developing-agent image on a sheet, a transfer voltage applied to transfer the developing-agent image onto the sheet, etc.
As a method for changing the operating state of the printing apparatus in accordance with the kind of the sheet being used, a method is known in which information for setting the operating state of the printing apparatus (hereinafter called operation information) is stored in the printing apparatus in association with the kind of sheet in advance. In addition, a method in which the operation information is generated by a host computer and is stored in the printing apparatus is also known (refer to, for example, Japanese Patent Laid-Open No. 2002-29120).
On the other hand, a system including a plurality of printing apparatuses for printing images on sheets has recently become popular. In such a system, the appearances of images printed in printing processes performed by different printing apparatuses can be nonuniform. This becomes a problem when, for example, a plurality of printing apparatuses perform printing processes using the same document data. More specifically, there may be a case in which sheets having images printed thereon using a plurality of printing apparatus are collected and delivered to a single client. In such a case, there is a risk that sheets having different appearances will be delivered. This problem can be solved by, for example, operating the printing apparatuses so as to adjust the operating states thereof such that images having a uniform appearance can be obtained in the printing processes performed individually by the printing apparatuses. However, when, for example, the appearance of an image printed on a sheet by a certain printing apparatus is to be matched with the appearance of an image printed on a sheet by another printing apparatus, a cumbersome task is required for setting the other printing apparatus. Therefore, to reduce the cumbersome task, a method of transmitting the operation information from a certain printing apparatus to another printing apparatus and matching the operating states of the two printing apparatuses can be used.
However, when the operation information is simply transmitted from one printing apparatus to another printing apparatus, the following problem occurs. That is, depending on the printing apparatus that receives paper information including the operation information, a failure occurs when the operation information included in the paper information is used. For example, if the kind of the printing apparatus that transmits the paper information is different from the kind of the printing apparatus that receives the paper information, a failure can occur in a printing process using the operation information included in the received paper information. Such a failure occurs when, for example, a fixing temperature indicated by the operation information included in the paper information cannot be set in the printing apparatus that received the paper information.